Gulf Coast Kangaroo Rats are confined to barrier islands of northeastern Mexico and southern Texas and the nearby Texas mainland. No fossils of this species have been found, but because of features of its teeth and skull, scientists think it is the most primitive living species of kangaroo rat. It has five toes on each hind foot, unlike most kangaroo rats, which have four. Seeds are its main food, although it also eats insects. Unlike Ord's Kangaroo Rat, which shares part of its range, it can take advantage of areas that have been cleared for farming and ranching. It must have soft soil to dig its burrows, however, whereas Ord's Kangaroo Rat usually lives where the soil is hard-packed and vegetation is thick.